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Models of fluidized granular materials: examples of non-equilibrium stationary states

Andrea Puglisi·Fabio Cecconi·Angelo Vulpiani
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Abstract

We review some models of granular materials fluidized by means of external forces such as: random homogeneous forcing with damping, vibrating plates, flow in an inclined channel and flow in a double well potential. All these systems show the presence of density correlations and non-Gaussian velocity distributions. These models are useful to understand the role of a kinetically defined ``temperature'' (in this case the so-called {\em granular temperature}) in a non-equilibrium stationary state. In the homogeneously randomly driven gas the granular temperature is {\em different} from that of the driving bath. Moreover two different granular materials mixed together may stay in a stationary state with different temperatures. At the same time, granular temperature determines (as in equilibrium systems) the escape time from a well in a double well potential.

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Andrea Puglisi, Fabio Cecconi, Angelo Vulpiani. 2005-01-20. Models of fluidized granular materials: examples of non-equilibrium stationary states. https://doi.org/10.1088/0953-8984%2F17%2F24%2F022

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